Posts for tag: x-rays
Radiographic (x-ray) images are an indispensible diagnostic tool in dentistry. One of the most routine and useful types of x-rays dentists take is the so-called bitewing. Here are some things you may want to know about this common diagnostic procedure.
What are bitewing x-rays?
Bitewings reveal the presence and extent of decay in the back teeth, specifically in areas where adjacent teeth touch each other. Unlike other areas of the teeth, these contacting surfaces between adjacent teeth can’t be examined visually. Bitewings can also show areas of bone loss around teeth — a sign of periodontal disease; however, they are not taken for that purpose because bitewings will not show the complete root surface that is surrounded by bone.
Why are they called that?
The name “bitewing” refers to how the film — or sensor, in the case of a digital x-ray — is positioned in the mouth: The patient bites down on a little tab or wing that holds the apparatus in place.
How often do I need them?
This is determined on a case-by-case basis, with the goal of not exposing you to any more radiation than necessary — even the minimal amount found in a series of bitewing x-rays. Your individual susceptibility to caries (tooth decay) and personal dental history will play a major role in determining how frequently you need radiographic examination — and, for that matter, how often you need to come in for routine cleanings and exams.
Are they safe?
The safety of bitewing x-rays is best illustrated with a comparison to the regular daily radiation exposure we get every day from environmental sources, which is about 0.01 millisieverts — the unit of measure we use for radiation. A series of 4 bitewing x-rays exposes you to 0.004 millisieverts of radiation — less than half of the daily exposure. Undetected tooth decay, which can spread quickly through the softer inner layers of teeth, is considered much more dangerous!
If a bitewing x-ray shows that there is tooth decay, what happens next?
If the cavity is very small, we may be able to treat it during the same appointment. If not, we will make a separate appointment to make sure it is taken care of promptly. The sooner tooth decay is treated, the better!
Your dental care would be much more limited without our ability to see “below the surface” with x-ray imaging. But since x-rays passing through the body are a form of radiation, could your exposure from them be hazardous to your health?
It depends on exposure dosages and, of course, the amount you have been exposed to over your lifetime. But, decades of research have demonstrated that exposure to dental x-rays during your regular office visits are only a fraction of the radiation you normally encounter from the natural environment every year.
X-rays have the ability to pass through body tissues, but at different rates for soft tissue like skin and muscle and hard tissue like bone. This effect creates shadows on exposed film; the differentiation is in such detail that a trained technician can interpret not only internal structures, but defects such as fractured bone or, in the case of dentistry, signs of tooth decay and bone loss from gum disease.
But like other energy sources in our environment, x-rays do emit radiation that in high doses can be dangerous to living tissue. The amount of exposure is measured in millisieverts (mSv), a unit that allows for comparison of doses from different sources of radiation. Scientists have calculated that we’re normally exposed to between 2 and 4.5 mSv every year.
By contrast, a single digital periapical image taken of a tooth is equal to 1 microsievert (μSv), or one thousandth of an mSv; a full mouth series (between 18 and 20 images) creates an exposure of 85 μSv, or 85/1000 of one mSv. In addition, advances in technology have further reduced the radiation exposure from x-ray imaging. For example, digital imaging has reduced exposure during full mouth x-rays from seven to ten days of equal exposure from normal background radiation to half a day, and with no loss in image quality.
In effect, dental x-rays pose little to no risk for patients. Still, understanding that x-ray imaging does expose patients to radiation, dentists follow certain protocols and safety precautions. For example, dentists will place a lead apron around their patients’ chest area during an x-ray exposure.
As your dentist, we’re happy to address any concerns you may have about x-ray radiation exposure. But rest assured, the x-ray devices used in your dental care, so necessary in the fight against tooth decay and other diseases, are safe and reliable.
If you would like more information on the use of x-ray technology and safety, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “X-Ray Frequency and Safety.”
Yes, dental x-rays are a safe and vital tool we use for measuring and monitoring your oral health. We feel it is imperative to ensure that our patients have the facts — especially when it comes to their oral healthcare. This is why we want to respond to this important question about the safety of dental x-rays.
We want you to know what they are, how they are used, what makes them a safe and effective tool, and why they are so important to dentistry and your health. X-rays are a form of electromagnetic radiation, in fact, just like natural daylight, except they have a much shorter wavelength. And because they are a form of ionizing radiation, they can easily penetrate bodily tissues without causing any harm when used properly. The reasons we use them are obvious; they help us literally see what is unseen. For example, they enable us to see bone structure and roots of teeth among other things, and are commonly used for diagnosing tooth decay. Furthermore, today's x-ray machines and other image capturing techniques are so sophisticated and sensitive that the amount of radiation required for diagnosis is almost nothing when compared to what you get from the background radiation present in everyday living. In fact, the average single digital periapical (“peri” – around; “apical” – root end of a tooth) film is equal to 1/10 the amount of everyday natural environmental exposure. These facts make it clear that dental x-rays are completely safe and, thus, are nothing you need to be concerned about.